Tethering: Turn off Wi-Fi Hotspot after inactivity (1/3)

Turn off the Wi-Fi hotspot after a specified time of inactivity.
The hotspot is considered to be inactive when no clients are
connected to it.

Change-Id: Ife48d5254b06b4e80841d5970984ab9979574e07

2 files changed, 60 insertions, 0 deletions

diff --git a/services/core/java/com/android/server/connectivity/Tethering.java b/services/core/java/com/android/server/connectivity/Tethering.java
index b9bbd8c..3472db2 100644
--- a/services/core/java/com/android/server/connectivity/Tethering.java
+++ b/services/core/java/com/android/server/connectivity/Tethering.java
@@ -36,8 +36,11 @@ import android.net.Network;
 import android.net.NetworkInfo;
 import android.net.NetworkUtils;
 import android.net.RouteInfo;
+import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiDevice;
+import android.net.wifi.WifiManager;
 import android.os.Binder;
+import android.os.Handler;
 import android.os.INetworkManagementService;
 import android.os.Looper;
 import android.os.Message;
@@ -164,12 +167,16 @@ public class Tethering extends BaseNetworkObserver {
     private static final int DNSMASQ_POLLING_INTERVAL = 1000;
     private static final int DNSMASQ_POLLING_MAX_TIMES = 10;
 
+    private long mWiFiApInactivityTimeout;
+    private final Handler mHandler;
+
     public Tethering(Context context, INetworkManagementService nmService,
             INetworkStatsService statsService, Looper looper) {
         mContext = context;
         mNMService = nmService;
         mStatsService = statsService;
         mLooper = looper;
+        mHandler = new Handler(mLooper);
 
         mPublicSync = new Object();
 
@@ -269,6 +276,18 @@ public class Tethering extends BaseNetworkObserver {
                     sm = new TetherInterfaceSM(iface, mLooper, usb);
                     mIfaces.put(iface, sm);
                     sm.start();
+                    if (isWifi(iface)) {
+                        // check if the user has specified an inactivity timeout for wifi AP and
+                        // if so schedule the timeout
+                        final WifiManager wm =
+                                (WifiManager) mContext.getSystemService(Context.WIFI_SERVICE);
+                        final WifiConfiguration apConfig = wm.getWifiApConfiguration();
+                        mWiFiApInactivityTimeout =
+                                apConfig != null ? apConfig.wifiApInactivityTimeout : 0;
+                        if (mWiFiApInactivityTimeout > 0 && mL2ConnectedDeviceMap.size() == 0) {
+                            scheduleInactivityTimeout();
+                        }
+                    }
                 }
             } else {
                 if (isUsb(iface)) {
@@ -278,6 +297,9 @@ public class Tethering extends BaseNetworkObserver {
                 } else if (sm != null) {
                     sm.sendMessage(TetherInterfaceSM.CMD_INTERFACE_DOWN);
                     mIfaces.remove(iface);
+                    if (isWifi(iface)) {
+                        cancelInactivityTimeout();
+                    }
                 }
             }
         }
@@ -428,6 +450,29 @@ public class Tethering extends BaseNetworkObserver {
         return result;
     }
 
+    private final Runnable mDisableWifiApRunnable = new Runnable() {
+        @Override
+        public void run() {
+            if (VDBG) Log.d(TAG, "Turning off hotpost due to inactivity");
+            final WifiManager wifiManager =
+                    (WifiManager) mContext.getSystemService(Context.WIFI_SERVICE);
+            wifiManager.setWifiApEnabled(null, false);
+        }
+    };
+
+    private void scheduleInactivityTimeout() {
+        if (mWiFiApInactivityTimeout > 0) {
+            if (VDBG) Log.d(TAG, "scheduleInactivityTimeout: " + mWiFiApInactivityTimeout);
+            mHandler.removeCallbacks(mDisableWifiApRunnable);
+            mHandler.postDelayed(mDisableWifiApRunnable, mWiFiApInactivityTimeout);
+        }
+    }
+
+    private void cancelInactivityTimeout() {
+        if (VDBG) Log.d(TAG, "cancelInactivityTimeout");
+        mHandler.removeCallbacks(mDisableWifiApRunnable);
+    }
+
     /*
      * DnsmasqThread is used to read the Device info from dnsmasq.
      */
@@ -511,10 +556,15 @@ public class Tethering extends BaseNetworkObserver {
                     new DnsmasqThread(this, device,
                         DNSMASQ_POLLING_INTERVAL, DNSMASQ_POLLING_MAX_TIMES).start();
                 }
+                cancelInactivityTimeout();
             } else if (device.deviceState == WifiDevice.DISCONNECTED) {
                 mL2ConnectedDeviceMap.remove(device.deviceAddress);
                 mConnectedDeviceMap.remove(device.deviceAddress);
                 sendTetherConnectStateChangedBroadcast();
+                // schedule inactivity timeout if non-zero and no more devices are connected
+                if (mWiFiApInactivityTimeout > 0 && mL2ConnectedDeviceMap.size() == 0) {
+                    scheduleInactivityTimeout();
+                }
             }
         } catch (IllegalArgumentException ex) {
             Log.e(TAG, "WifiDevice IllegalArgument: " + ex);
diff --git a/wifi/java/android/net/wifi/WifiConfiguration.java b/wifi/java/android/net/wifi/WifiConfiguration.java
index 9d4f6e2..35d6d9e 100644
--- a/wifi/java/android/net/wifi/WifiConfiguration.java
+++ b/wifi/java/android/net/wifi/WifiConfiguration.java
@@ -456,6 +456,13 @@ public class WifiConfiguration implements Parcelable {
      */
     public int userApproved = USER_UNSPECIFIED;
 
+    /**
+     * @hide
+     * Inactivity time before wifi tethering is disabled.  Here inactivity means no clients
+     * connected.  A value of 0 means the AP will not be disabled when there is no activity
+     */
+    public long wifiApInactivityTimeout;
+
     /** The Below RSSI thresholds are used to configure AutoJoin
      *  - GOOD/LOW/BAD thresholds are used so as to calculate link score
      *  - UNWANTED_SOFT are used by the blacklisting logic so as to handle
@@ -1556,6 +1563,7 @@ public class WifiConfiguration implements Parcelable {
             creationTime = source.creationTime;
             updateTime = source.updateTime;
             SIMNum = source.SIMNum;
+            wifiApInactivityTimeout = source.wifiApInactivityTimeout;
         }
     }
 
@@ -1638,6 +1646,7 @@ public class WifiConfiguration implements Parcelable {
         dest.writeInt(numNoInternetAccessReports);
         dest.writeInt(noInternetAccessExpected ? 1 : 0);
         dest.writeInt(SIMNum);
+        dest.writeLong(wifiApInactivityTimeout);
     }
 
     /** Implement the Parcelable interface {@hide} */
@@ -1717,6 +1726,7 @@ public class WifiConfiguration implements Parcelable {
                 config.numNoInternetAccessReports = in.readInt();
                 config.noInternetAccessExpected = in.readInt() != 0;
                 config.SIMNum = in.readInt();
+                config.wifiApInactivityTimeout = in.readLong();
                 return config;
             }